Researchers at Texas A&M Plan Interdisciplinary Chagas Disease Research Program
COLLEGE STATION, Texas – A Texas A&M University team of researchers plans to approach research on Chagas disease from an ecological perspective. They will look at how environmental factors, such as climate and land cover, and socioeconomic factors, such as housing conditions, affect the distribution of the disease. As the disease is primarily transmitted by insects called kissing bugs, any factor that influences kissing bug abundance or behavior will also impact disease risk. For example, poor housing conditions allow kissing bugs to colonize the home and increase the opportunity for them to take a blood meal from a sleeping human. Furthermore, as the climate changes, the distribution of the kissing bugs can shift, which could lead to the emergence of Chagas disease in new areas of the United States.
Chagas disease, which affects approximately eight million people in the Americas, according to the United States Centers for Disease Control and Prevention, is caused by the parasite Trypanosoma cruzi and is spread by kissing bugs that are prevalent across North, Central, and South America. Although once thought to be only a tropical disease, there is a current problem of canine Chagas disease in many regions of Texas that affects working dogs (such as military or border patrol), prized purebred breeding and show dogs, household pets, and stray dogs. In addition to the humans and dogs affected, the disease has been reported in South America in both cattle and pigs, and thus has the potential to threaten the economic stability of those who rely on livestock. Between 30 and 40 percent of those infected will develop life-threatening heart disease.
In addition to the cardiac complications, humans can also experience intestinal complications and even-especially in young children-meningoencephalitis, which is a life-threating inflammation of the brain.
The team’s research proposal, chosen through a competitive process, is one of only four to receive funding through the Texas A&M One Health Grand Challenge. It is a collaboration of faculty members in six Texas A&M colleges: Gabriel Hamer at the College of Agriculture and Life Sciences, Cecilia Giusti at the College of Architecture, Dan Goldberg at the College of Geosciences, Charles Criscione at the College of Science, Sarah Hamer at the Veterinary Medicine & Biomedical Sciences (CVM), and Ann Millard at the School of Public Health at the Health Science Center. Together, they have expertise in ecology, epidemiology, population genetics, parasitology, community health, border health, medical anthropology, medical and veterinary entomology, land and economic development and planning, Latin American studies, and spatial analysis.
“Zoonotic diseases are the ultimate One Health challenge because of the complex interactions among humans, wildlife, domestic animals, vectors, and pathogens within shared environments,” said Dr. Sarah Hamer, an assistant professor in the College of Veterinary Medicine & Biomedical Sciences (CVM) and the principal investigator on the project. “We plan for our research and outreach on Chagas disease to serve as ‘proof of principle,’ and that our One Health approach will be extended to tackle other vector-borne zoonotic disease systems in the future. We are in a great place for Texas A&M University to be a leader in multidisciplinary vector-borne disease research.”
The team plans a three-pronged approach to their research in south Texas. First, they will trap kissing bugs, collect wildlife, domestic animal, and human blood samples, and assess the socioeconomic environment. Then, they will process samples in the laboratory to sequence DNA and determine the population genetics of both the parasites and the kissing bugs that transmit them. Finally, they will use that information to map the disease over time and space, taking into account the relationships between environmental, climatic, and demographic factors that influence spread and severity of disease. This map will then serve as a basis for future research, as it can help identify risk factors and evaluate intervention strategies.
“This research program represents well what the One Health Grand Challenge at Texas A&M University is all about,” said Dr. Eleanor M. Green, the Carl B. King Dean of Veterinary Medicine at the CVM. “Facilitated by Dr. Michael Chaddock, assistant dean for One Health, investigators came together from across campus to form the research team dedicated to finding extraordinary solutions for this disease of importance to Texas and beyond. Equally impressive is the funding of this project, which was also a team approach. Dr. Glen Laine, vice president for research at Texas A&M, matched voluntary contributions from the involved colleges to fully fund this challenge proposal.”
Although there is a recent increase in awareness of Chagas disease in Texas, researchers believe Chagas disease has existed in the Southern U.S. for a long time. In fact, mummified remains of humans from Texas and South America who died more than 1,150 years ago have evidence of Chagas disease.
“This devastating disease is one of several neglected tropical diseases that can increase the poverty in already disadvantaged regions as it can have impacts on child development and worker productivity,” said Dr. Michael Chaddock. “As an under-diagnosed, under-reported disease with poorly-understood risk factors, this type of research is desperately needed.”
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About the Texas A&M One Health Initiative: The initiative is dedicated to the discovery, development, communication, and application of knowledge in a wide range of academic and professional fields providing the highest quality undergraduate, graduate and professional programs to prepare students to assume roles in leadership, responsibility and service to society. It builds on the strength of the university and the state of Texas from discovery to application and commercialization allowing for the discovery, learning and applied research to meet societal needs. Learn more about the One Health Initiative at http://onehealth.tamu.edu.